It's when the bees top moving old wax around and start making new wax. Usually just before the main flow. But you can get some earlier if you put empty frames in the brood nest.

OK this is probably a silly question. Michael you said "when the bees stop moving old wax around..."..do the bees reuse wax in their hive? Like I guess when they are rebuilding the comb that may have been damaged by extracting honey. Do they reuse this wax, if so, how on earth do they do it? do they chew it up and put it to rebuild? Great day. Cindi

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There are strange things done in the midnight sun by the men who moil for gold. The Arctic trails have their secret tales that would make your blood run cold. The Northern Lights have seen queer sights, but the queerest they ever did see, what the night on the marge of Lake Lebarge, I cremated Sam McGee. Robert Service

Yes the bees move wax around, especially in the early spring. Oddly they never seem to take it from anywhere except old perfectly good comb. I've left cappings out many times and they only clean up the honey and never seem to take any significant amount of wax. They just chew it up and put it where they want it.